Roughly chop the chocolate and melt in a water bath. In a bowl, cream the butter with the sugar using a hand mixer.
Stir in the eggs and then the liquid chocolate. Preheat the oven to 200 degrees.
Mix the flour with baking powder, nuts, salt and vanilla and mix with the wet ingredients until a creamy dough is formed. Grease a baking dish of about 20 x 10 cm and pour in the batter.
Then bake the smooth batter for about 30 minutes at 180 degrees, or until it passes the stick test. Cut the brownies into 3 x 2 cm pieces and enjoy them while they are still warm. The recipe comes from an American cookbook.